Have there ever been instances in which you have gotten to within a few feet in front of an Imp face to face, aim your shotgun right square at him, pulled the trigger, and not killed him? Every once and a while this happens to me no matter what port I'm using, if one at all.

Is there some piece of code in the engine that accounts for this or is it just a random occurance or something?

It sucks. It seems to happen to me all the time. It's especially annoying when I run up to an almost-dead hell knight, baron or revenant, shoot the shotgun point-blank into the very center of the dude, and maybe two drips of blood fall and about 18 pellets hit the wall behind the guy. Then of course I get my ass kicked.

With this example, the damage done is at least 5 and at most 15, could be anything in between though.

a = 4
b = 9

This would be at least 4 and at most 36.

a = 15
b = 10

This would be at least 15 and at most 150.

Get it? If the weapons don't seem to do consistent damage its because they don't. This is why sometimes you can survive a rocket to the face with zero armor and most times you can't. It puts a little bit of randomness into the mix.

Maybe you were running towards the imp, and the shotgun sprite was shifted all the way to the right or left. Then you lined the enemy up with the sprite, and the pellets missed because you were aiming off-center.

Thanks deadnail. I assume that those charts that I occasionally stumble upon which state that it takes one shotgun blast to take care of an Imp, seven for a Cacodemon, two for a Demon, etc. can be somewhat ignored.

Maybe you were running towards the imp, and the shotgun sprite was shifted all the way to the right or left. Then you lined the enemy up with the sprite, and the pellets missed because you were aiming off-center.

Definetly possible, and it has happened to me before, although the instances I have in mind were ones in which I was CERTAIN that I had the barrel pointed right at him, not the sprite.

Thats a possibility. Thats why those lovely things called crosshairs were invented. :)

When I play I aim according to where the barrel's pointed, i.e. horizontally only, like the original DOOM.